Machines for cutting leaf tobacco



April 12, 1966 H. WARD MACHINES FOR CUTTING LEAF TOBACCO 2 Sheets-Sheet 1 Filed April 13, 1964 [no n! f/IKV M444 Wk Attorneys April 12, 1966 WARD 3,245,301

MACHINES FOR CUTTING LEAF TOBACCO Filed April 13, 1964 2 Sheets-Sheet 2 United States Patent C) 3,245,301 MACHINES FOR CUTTING LEAF TOBACCO Harry Ward, London, England, assiguor, by rnesne assignments, to AMF International Limited, London, England Filed Apr. 13, 1964, Ser. No. 359,093 Claims priority, application Great Britain, Apr. 17, 1963, 15,114/ 63 7 Claims. (Cl. 83355) It is desirable to have a shearing action between the knives and the front of the bottom member of the mouthpiece. In the event of a slight mis-positioning of the cutter, there is then less danger of damage being caused to the knives by a direct abutment of their cutting edges against the bottom member of the mouthpiece, because the lengths of the cutting edges of the knives tend to be led from the mouthpiece sides over the front edge of the bottom mouthpiece member.

It may also be desirable to have a similar shearing action between the knives and the front face of the top member of the mouthpiece, so that the cutting force of the cutter is spread more evenly through time than if there is no such shearing action, and jarring of the knife feeding mechanism and the bearings supporting the cutter is minimised.

According to this invention, in a machine of the type described, the bottom member of the mouthpiece has a V-shaped top surface across its width, extending back from its front face, the arms of the V pointing upwards, and the cutter rotates in a direction such that the cutting edges of the knives pass down across the front face of the mouthpiece, passing the ends of the arms of the V first and the vertex of the V last. The vertex of the V extends substantially perpendicularly from the front face of the mouthpiece, and the depth of the V is only a fraction of its width. Preferably, the V-shaped top surface is stopped short of the rear face of the member, and the top surface of the rear part of the member is fiat, and horizontal.

Use of such a bottom member of the mouthpiece having a V-shaped top surface provides a shear cutting action between the cutting edges of the knives of the rotating cutter and the front face of the bottom member of the mounthpiece, even if the cutting edges of the knives are arranged substantially parallel to the axis of the rotat ing cutter. The rotating cutter can be made considerably more economically if the knives are set with their cutting edges parallel to the axis, than if the cutting edges are arranged at a skew angle with respect to the axis of the cutter.

The top member of the mouthpiece may have a flat bottom surface. The depth of the mouth of the mouthpiece is then greater at its middle than at its sides, and this is an advantage because the quantity of tobacco fed to the mouthpiece tends to be greater at the middle than at the sides, and so the tobacco may pass through the mouthpiece at a substantially uniform density across the width of the mouthpiece.

Alternatively, the top member may have a V-shaped bottom surface across its width extending back from its front face, this V-shaped surface matching that of the bottom member. The aperture or mouth formed between the bottom and top members is thus of chevron form.

Such a mouthpiece provides a shear cutting action between the knives and the front face of the top member of the mouthpiece, even if the cutting edges of the knives are arranged substantially parallel to the axis of the cylindrical cutter on which the knives are mounted.

A machine including a mouthpiece according to the invention will now be described by way of example with reference to the accompanying drawings, of which:

FIGURE 1 is a sectional side elevational view of part of the tobacco cutting machine;

FIGURE 2 is a front view of the dead plate which forms the. major part of the top surface of the bottom member of the mouthpiece;

FIGURE 3 is a plan View of the dead plate shown in FIGURE 2;

' FIGURE 4 is a front view of the knock-off member which forms the front portion of the bottom member of the mouthpiece.

With reference to FIGURE 1, the tobacco cutting machine comprises a rotating cutter having knives such as indicated at 2 whose cutting edges move in a cylindrical path indicated by the broken line 4 which touches or nearly touches the front face of the mouthpiece. The mouthpiece comprises a top member 6, and a bottom member 8. Tobacco is fed between an upper conveyor indicated at 9 and a lower conveyor indicated at 9a to and through the mouthpiece, in order to be cut by the knives of the rotating cutter.

The knives of the rota-ting cutter are mounted with their cutting edges parallel to the axis of the rotating cutter.

The bottom member 8 of the mouthpiece comprises a dead plate 10, a knock-off member 12, and a support member 14. The dead plate is attached to the top of the support member 14 by means of screws 16. The knock-off member 12 is attached to the support member 14 by means of three shear screws 18, and the rear face of the knock-off member 12 has an upward pointing step 20 having an upwardly inclined upper surface, which step meets with a corresponding downward pointing step 22 formed in the front face of the dead plate 10.

The front part of the top surface of the bottom member 8 of the mouthpiece is thus formed by the top surface of the knock-off member 12, and the rear part is formed by the top surface of the dead plate 10. As shown in FIGURES 2, 3 and 4, the top surfaces of the dead plate It and the knock-off member 12 are both formed with a V, so that the bottom member 8 of the mouthpiece has a V-shaped top surface across its width, extending back from its front face. The depth of the V is indicated at 24 in FIGURE 2, and as shown the arms of the V point upwards. The cutter rotates in a direction such that the cutting edges of the knives pass down across the face of the mouthpiece, passing the ends of the arms of the V formed in the knock-01f member 12 first, and the vertex of the V last.

As shown in FIGURE 3, the V-shaped top surface of the dead plate 10 is stoped short of the rear face of the dead plate, along the lines 26 and 28. The rear part of the dead plate 30 has a flat top surface.

The vertex of the X extends substantially perpendicularly from the front face of the knock-off member 12 of the mouthpiece, and as shown in FIGURE 2 the depth of the V is only a fraction of its width.

The edges of the front face of the knock-off member 12 are formed with ears 32 and 34 as shown in FIG- URE 4, which are machined in conjunction with corresponding ears 36 and 38 formed at the edges of the dead plate 10.

A mouthpiece having a V-shaped top surface of the bottom member according to the invention leads to more efllcient cutting of the tobacco than a mouthpiece having a bottom member with its top surface inclined in one direction only. In such a mouthpiece tobacco is likely to be left uncut at the side on which the top surface is the lower, whereas in the present arrangement, with the lowest point on the top surface in the middle of the mouthpiece, this does not occur.

I claim:

1. A tobacco cutting machine comprising a mouth having a bottom member and a top member, a cutter with knives mounted for rotation across said mouth, said bottom member of the mouthpiece having a V-shaped top surface across its width, extending back from its front face, the arms of the V pointing upwards; and said cutter being mounted to rotate in a direction such that the cutting edges of the knives pass down across the front face of the mouthpiece, passing the ends of the arms of the V first and the vertex of the V last.

2. A machine according to claim 1 in which the vertex of the V extends substantially perpendicularly from the front face of the mouthpiece.

3. A machine according to claim 1 in which the depth of the V is only a fraction of its width.

4. A machine according to claim 1 in which the V- shaped top surface is stopped short of the rear face of the bottom member of the mouthpiece, and the top surface of the rear part of the bottom member is flat and horizontal.

5. A machine according to claim 1 in which the top member of the mouthpiece has a flat bottom surface.

6. A machine according to claim 1 in which the top member of the mouthpiece has a Vshaped bottom surface extending across its Width and back from its front face, this V-shaped surface matching that of the top surface of the bottom member of the mouthpiece.

7. A machine according to claim 1 in which the knives are mounted in the rotating cutter with their cutting edges parallel to the axis of the rotating cutter.

References Cited by the-Examiner UNITED STATES PATENTS 3/1956 Huck 8334l 9/1964 Spengler et al. 83694 X 

1. A TOBACCO CUTTING MACHINE COMPRISING A MOUTH HAVING A BOTTOM MEMBER AND A TOP MEMBER, A CUTTER WITH KNIVES MOUNTED FOR ROTATION ACROSS SAID MOUTH, SAID BOTTOM MEMBER OF THE MOUTHPIECE HAVING A V-SHAPED TOP SURFACE ACROSS ITS WIDTH, EXTENDING BACK FROM ITS FRONT FACE, THE ARMS OF THE V POINTING UPWARDS; AND SAID CUTTER BEING MOUNTED TO ROTATE IN A DIRECTION SUCH THAT THE CUTTING EDGES OF THE KNIVES PASS DOWN ACROSS THE FRONT FACE OF THE MOUTHPIECE, PASSING THE ENDS OF THE ARMS OF THE V FIRST AND THE VERTEX TO THE V LAST. 